'87 420SEL just died as I was riding down the street. No hiccup or anything. I was going down hill and did not notice I had lost engine power. I first noticed the power steering was not working but then I realized my power brakes went out. All the diagnostic lights on the dash lit up just as if I had put the key in and had turned the key to position one. I coasted to a parking spot; strange thing was the radio never shut off until I turned the ignition off, but then the car started up as normal and I drove home. I don’t know where to begin troubleshooting this problem as it right now is transient. The only thing I suspect is the ignition cylinder has been getting stuck more and more as I’m trying to turn on the engine and I’ve had to jiggle the key more to get it to turn. Can a contact be wearing out in the key cylinder that keeps the electrical flowing? Any other suggestion on where to begin troubleshooting would be appreciated.